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<FONT color="green">001</FONT>    /**<a name="line.1"></a>
<FONT color="green">002</FONT>    * Allows timing of the execution of any block of code.<a name="line.2"></a>
<FONT color="green">003</FONT>    */<a name="line.3"></a>
<FONT color="green">004</FONT>    <a name="line.4"></a>
<FONT color="green">005</FONT>    package org.hackystat.ui.sensordataviewer.server;<a name="line.5"></a>
<FONT color="green">006</FONT>    <a name="line.6"></a>
<FONT color="green">007</FONT>    /**<a name="line.7"></a>
<FONT color="green">008</FONT>     * A utility Stopwatch class which can provide timings for any section of code.<a name="line.8"></a>
<FONT color="green">009</FONT>     * @author David J. Nickles<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     */<a name="line.11"></a>
<FONT color="green">012</FONT>    public final class Stopwatch {<a name="line.12"></a>
<FONT color="green">013</FONT>      private long fStart;<a name="line.13"></a>
<FONT color="green">014</FONT>      private long fStop;<a name="line.14"></a>
<FONT color="green">015</FONT>    <a name="line.15"></a>
<FONT color="green">016</FONT>      private boolean fIsRunning;<a name="line.16"></a>
<FONT color="green">017</FONT>      private boolean fHasBeenUsedOnce;<a name="line.17"></a>
<FONT color="green">018</FONT>      <a name="line.18"></a>
<FONT color="green">019</FONT>      /**<a name="line.19"></a>
<FONT color="green">020</FONT>      * Start the stopwatch.<a name="line.20"></a>
<FONT color="green">021</FONT>      *<a name="line.21"></a>
<FONT color="green">022</FONT>      * @throws IllegalStateException if the stopwatch is already running.<a name="line.22"></a>
<FONT color="green">023</FONT>      */<a name="line.23"></a>
<FONT color="green">024</FONT>      public void start() {<a name="line.24"></a>
<FONT color="green">025</FONT>        if ( this.fIsRunning ) {<a name="line.25"></a>
<FONT color="green">026</FONT>          throw new IllegalStateException("Must stop before calling start again.");<a name="line.26"></a>
<FONT color="green">027</FONT>        }<a name="line.27"></a>
<FONT color="green">028</FONT>        //reset both start and stop<a name="line.28"></a>
<FONT color="green">029</FONT>        this.fStart = System.currentTimeMillis();<a name="line.29"></a>
<FONT color="green">030</FONT>        this.fStop = 0;<a name="line.30"></a>
<FONT color="green">031</FONT>        this.fIsRunning = true;<a name="line.31"></a>
<FONT color="green">032</FONT>        this.fHasBeenUsedOnce = true;<a name="line.32"></a>
<FONT color="green">033</FONT>      }<a name="line.33"></a>
<FONT color="green">034</FONT>    <a name="line.34"></a>
<FONT color="green">035</FONT>      /**<a name="line.35"></a>
<FONT color="green">036</FONT>      * Stop the stopwatch.<a name="line.36"></a>
<FONT color="green">037</FONT>      *<a name="line.37"></a>
<FONT color="green">038</FONT>      * @throws IllegalStateException if the stopwatch is not already running.<a name="line.38"></a>
<FONT color="green">039</FONT>      */<a name="line.39"></a>
<FONT color="green">040</FONT>      public void stop() {<a name="line.40"></a>
<FONT color="green">041</FONT>        if ( !this.fIsRunning ) {<a name="line.41"></a>
<FONT color="green">042</FONT>          throw new IllegalStateException("Cannot stop if not currently running.");<a name="line.42"></a>
<FONT color="green">043</FONT>        }<a name="line.43"></a>
<FONT color="green">044</FONT>        this.fStop = System.currentTimeMillis();<a name="line.44"></a>
<FONT color="green">045</FONT>        this.fIsRunning = false;<a name="line.45"></a>
<FONT color="green">046</FONT>      }<a name="line.46"></a>
<FONT color="green">047</FONT>    <a name="line.47"></a>
<FONT color="green">048</FONT>      /**<a name="line.48"></a>
<FONT color="green">049</FONT>      * Express the "reading" on the stopwatch.<a name="line.49"></a>
<FONT color="green">050</FONT>      *<a name="line.50"></a>
<FONT color="green">051</FONT>      * @throws IllegalStateException if the Stopwatch has never been used,<a name="line.51"></a>
<FONT color="green">052</FONT>      * or if the stopwatch is still running.<a name="line.52"></a>
<FONT color="green">053</FONT>      * @return the current milliseconds readout from this stopwatch instance<a name="line.53"></a>
<FONT color="green">054</FONT>      */<a name="line.54"></a>
<FONT color="green">055</FONT>      public String toString() {<a name="line.55"></a>
<FONT color="green">056</FONT>        validateIsReadable();<a name="line.56"></a>
<FONT color="green">057</FONT>        StringBuffer result = new StringBuffer();<a name="line.57"></a>
<FONT color="green">058</FONT>        result.append(this.toValue());<a name="line.58"></a>
<FONT color="green">059</FONT>        result.append(" ms");<a name="line.59"></a>
<FONT color="green">060</FONT>        return result.toString();<a name="line.60"></a>
<FONT color="green">061</FONT>      }<a name="line.61"></a>
<FONT color="green">062</FONT>    <a name="line.62"></a>
<FONT color="green">063</FONT>      /**<a name="line.63"></a>
<FONT color="green">064</FONT>      * Express the "reading" on the stopwatch as a numeric type.<a name="line.64"></a>
<FONT color="green">065</FONT>      *<a name="line.65"></a>
<FONT color="green">066</FONT>      * @throws IllegalStateException if the Stopwatch has never been used,<a name="line.66"></a>
<FONT color="green">067</FONT>      * or if the stopwatch is still running.<a name="line.67"></a>
<FONT color="green">068</FONT>      * @return the current milliseconds readout from this stopwatch instance<a name="line.68"></a>
<FONT color="green">069</FONT>      */<a name="line.69"></a>
<FONT color="green">070</FONT>      public long toValue() {<a name="line.70"></a>
<FONT color="green">071</FONT>        validateIsReadable();<a name="line.71"></a>
<FONT color="green">072</FONT>        return this.fStop - this.fStart;<a name="line.72"></a>
<FONT color="green">073</FONT>      }<a name="line.73"></a>
<FONT color="green">074</FONT>    <a name="line.74"></a>
<FONT color="green">075</FONT>      /**<a name="line.75"></a>
<FONT color="green">076</FONT>      * Throws IllegalStateException if the watch has never been started,<a name="line.76"></a>
<FONT color="green">077</FONT>      * or if the watch is still running.<a name="line.77"></a>
<FONT color="green">078</FONT>      */<a name="line.78"></a>
<FONT color="green">079</FONT>      private void validateIsReadable() {<a name="line.79"></a>
<FONT color="green">080</FONT>        if ( fIsRunning ) {<a name="line.80"></a>
<FONT color="green">081</FONT>          String message = "Cannot read a stopwatch which is still running.";<a name="line.81"></a>
<FONT color="green">082</FONT>          throw new IllegalStateException(message);<a name="line.82"></a>
<FONT color="green">083</FONT>        }<a name="line.83"></a>
<FONT color="green">084</FONT>        if ( !fHasBeenUsedOnce ) {<a name="line.84"></a>
<FONT color="green">085</FONT>          String message = "Cannot read a stopwatch which has never been started.";<a name="line.85"></a>
<FONT color="green">086</FONT>          throw new IllegalStateException(message);<a name="line.86"></a>
<FONT color="green">087</FONT>        }<a name="line.87"></a>
<FONT color="green">088</FONT>      }<a name="line.88"></a>
<FONT color="green">089</FONT>    }<a name="line.89"></a>




























































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